RojoRacing
Donut Powered Wise-guy
The power isn't free, you only have so much energy in the body and only so much power from each muscle. If you were gaining 6.5% in efficiency that would be another story but we're not.
Climbing hills on a V20?
- Thread starter Osiris
- Start date
The power isn't free, you only have so much energy in the body and only so much power from each muscle. If you were gaining 6.5% in efficiency that would be another story but we're not.
murmur
Member
Serpentine isn't for the long haul, as far as I can tell. It's only for low speeds, which is ok for us recumbents since sprinting isn't something we do a lot of.
In cardio-limited situations, serpentine isn't going to gain you much, but otherwise it's a free increase in recruitable muscle mass. Presumably you're only going to use serpentine when you're already at or near your maximum (efficient) leg-power, where adding any more leg power is going to quickly put you into the "red". If you can add some arms/core wattage at an efficient level (maybe 30% of the maximum from those muscles) then it would be silly not to, up to your cardio limitation.
LarryOz
Cruzeum Curator & Sigma Wrangler
Exactly Jason!
This is one of the best statements in this Thread! If you are really racing and maxed out at your LT, then even if you arm muscles are rested, you aerobic system will not really allow you to apply more power/energy. Best you can do is use your upper body for a minute or 2 and let you legs rest maybe a few %, then your arms will be fatigued. They cannot work as hard as your big legs! That is about all you will get - maybe every 10-15 minutes. Still something is better than nothing.
Osiris
Zen MBB Master
No, these are numbers read directly from my power meter, which happens to be the same Garmin Vector power meter Larry uses. I've been looking at Larry's numbers for quite some time, and find them very puzzling. His results on the V20 compare pretty closely to those I've obtained on my M5, but the numbers comparing my V20 to his are miles apart. Larry's bike is equipped with all sorts of go-fast stuff like a disk wheel, narrow custom handlebars, etc., while mine is stock, so that will account for some of the difference. I've checked for things like brake drag or a dry chain that might be slowing me down, but I haven't found anything unusual. At any rate, power production plays no role in coast down results, and they show the M5 having a huge aerodynamic advantage over the V20, even at relatively modest speeds of around 20 mph. To be perfectly candid, this is the only reason I've decided to hang on to the M5.
Edit: I had a look at another one of my results with the V20 on the mile long segment, this time helped by a very strong tailwind. The results then were an average speed of 26.9 mph @ 235 watts, which looks closer to what you and Larry are getting on windless days.
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Osiris
Zen MBB Master
Sure, but if I can produce 20 watts more for even a minute, it would be enough to grab all those uphill KOM's I haven't been able to win.
RojoRacing
Donut Powered Wise-guy
LarryOz
Cruzeum Curator & Sigma Wrangler
Yes, you wattage values appear to be very hi for that speed! 327 watts. Wow - how long was your "test" time, and where? closed loop track with no interruptions?
I also have an M5 CHR and my V20 beats it in every test I have done, but they are very close. Coast down, constant wattage and speed testing on a track during same day, same hour, same wheels, cranks, pedals, etc.
Are you capturing all this data on a closed loop and riding the same day? When I test, I also get up to speed at about the speed or wattage I want to test at and then hit the lap timer. They I ride for a predetermined time (or dist), say 5 minutes, 10 minutes etc. and keep an eye on the average wattage for the lap and adjust my effort accordingly to make it be whatever I am looking at. 250 watts for example. I usually do a range of different wattages at different distances, like 100-300 in 25 watt increments. Then I swap equipment to the other bike and repeat it right then.
Only thing I can think of is that you have some big aero drag on your V20 setup that you just cannot see. If possible, get on the bike and have someone take front rear and side views of you in your riding position. I am happy to take a look and offer suggestions.
LarryOz
Cruzeum Curator & Sigma Wrangler
20 watts added to 300 watts, say at 25mph is only 6.7% increase in wattage, which using aerodynamic speed/power formula will only yield a 1.7% increase in speed (1.7% of 25mph is only 0.4mph - still something, but over 1 mile it is only 0.037 minutes (or 2.2 seconds) and then only for as long as you can keep up full engagement of your upper body. I doubt most people could last more than a couple minutes. This mean for any KOM longer than 1 mile it may still only give you 2 seconds, and for most KOM's' under a mile I believe DF's have an greater advantage. OK -since we are talking KOM''s - I am reminded that this thread is about climbing on a V20 - On anything stepper than 3% grade I do not think a V20 (even with Jason riding it) will out climb a DF even with me riding it! V20 climbs great for a bent - the best of all of them for sure - but still can't climb steep stuff like a DF - sorry!Sure, but if I can produce 20 watts more for even a minute, it would be enough to grab all those uphill KOM's I haven't been able to win.
My 2 cents - and that is what it is worth! haha
Osiris
Zen MBB Master
I was going through my video uploads and found this one, which was taken on my CA2 a couple of months ago. I haven't ridden that road on my V20 yet, but all my tests so far show the V20 being dead even with the Ca2 in terms of speed/power. The same Vector 3 pedals that were on my CA2 are now on my V20. Take a look at the numbers displayed on screen:
LarryOz
Cruzeum Curator & Sigma Wrangler
I see - but can also see there was some climbing, etc. Hard to know what the wind was etc. Maybe if you rode the same route 30-40 times consecutive days and took a snip of the power data from the exact section for each day and averaged it, then did the same thing for the Vendetta you could compare numbers. As I said, all my number are from a closed loop track under very controlled conditions - two bikes at virtually the same time. Closed track with little to no elevation gain will yield the greatest speed also for given wattage. Find a high school track or something local and do some testing. Also double check your crank length on your cranks and in your Garmin. I have had my Garmin reset the P1 crank length to a default when I replace the batteries and/or re-connect and have gotten strange power readings before - usually high. Do you have a trainer like KICKR where you can compare what you P1 pedals are giving you and are accurate?
Osiris
Zen MBB Master
Well, until I retire, there's just no way I could ride the same route 30-40 times on consecutive days!
The coast-down tests tell the story. Power readings and drivetrain losses don't even factor into it: just start at the same speed and coast all the way down the hill. I've done it more times than I can count on the M5, and the numbers are always the same: 21.4 mph to 21.6 mph top speed. On the V20 I'm getting top speeds of 18.5 mph to 19.1 mph. That's with me wearing the same riding gear, same tires, and same tire pressures, just to make sure it's a fair comparison. I'm not going to obsess about squeezing more speed out of the V20 because I have no intention of racing it. If I want to set records, I'll do it on the M5 or possibly even the M1. The V20 will be the bent I'll be spending 95% of my time on, because it's easily the best recumbent I've ever ridden. In fact, I can do all my training rides on it because my focus is on wattage, not speed.
benphyr
Guru-me-not
I am glad you said that, I was starting to think that you were disappointed (sacrilege) in the V20.
benphyr
Guru-me-not
@Osiris
Do you have any pictures of you riding the V20 and M5: side, front, whatever. Maybe the collective tribe can find something that is causing the discrepancy. Maybe even get you in the ball-park of Watts per speed of the other V20 riders or at least clear up why there is such a difference. It bugs me to not know the difference even though I don't have a V20.!.
Cheers,
Ben.
Do you have any pictures of you riding the V20 and M5: side, front, whatever. Maybe the collective tribe can find something that is causing the discrepancy. Maybe even get you in the ball-park of Watts per speed of the other V20 riders or at least clear up why there is such a difference. It bugs me to not know the difference even though I don't have a V20.!.
Cheers,
Ben.
Sure, but if I can produce 20 watts more for even a minute, it would be enough to grab all those uphill KOM's I haven't been able to win.
Easier to lose some weight.
LarryOz
Cruzeum Curator & Sigma Wrangler
I would still encourage you to send us some pictures of you on the bikes. The power to speed "should" be pretty close, so something will stick out to us if we can see it and compare. Lots of knowledge in the collective Tribe here - put it to use!
Osiris
Zen MBB Master
I don't have any photos of the V20 yet. It's in the shop right now being fitted with Di2 electronic shifting, so I won't have it back until Friday at the earliest. All I can tell you is that it was at the time of testing completely stock, with the exception of a Ventisit seat pad. I can't see how the seat pad might be costing me 2 mph, though!
Osiris
Zen MBB Master
It's difficult to imagine how some aspect of my V20 could be causing a 2 mph+ discrepancy in these coast down tests. Even the brakes are adjusted so that there's a larger than average gap between the brake shoes and wheel rim, which eliminates brake drag as a possible culprit. Consider also that my results have been very consistent; it's not as if I had low tire pressures one day and not the other, or that I was facing a headwind, etc. Personally, I'm not the least surprised that the M5 has such a big aerodynamic advantage over the V20. The M5 was originally designed to beat the indoor hour record, which it did, so it's designers were willing to make lots of compromises for speed. I don't get that impression from looking at the V20. For starters, it has a very cluttered front end compared to the much sleeker M5. It's wide handlebars not only create quite a bit more drag than the M5's tiller, but also places the rider's arms out in the airstream. These are not features you want if the goal is to make the bike and rider as aerodynamic as possible.
Osiris
Zen MBB Master
The tests were either on consecutive days or one week apart. In the case of the M5 and CA2, I've been running these tests nearly every weekend since the Summer of 2015. If differences in air density played a significant role, I wouldn't be seeing the same results every time. Keep in mind also that we're not talking about very high speeds. 19 mph and 21 mph, respectively, are a good deal slower than my normal rolling speed.
LarryOz
Cruzeum Curator & Sigma Wrangler
As you can see this is a really wide opened question based on what we have said already. A lot really depends on how you fit on each bike.
I am 5'7" and the Vendetta fits me like a glove. It is almost like it was made for me and my size. I a really low CdA on it.
If you have a longer torso your head stick up more and will have a lower speed per wattage figure. (on am M5 CHR maybe not stick up as much since is is built for taller people)
3 1/2 years ago I ran a test on Northbrook track between my Vendetta and an M5-midracer which had a 650 front wheel. I switched out all I could so stuff was as close as it could be: Rear wheel, cranks, pedals. I also fit on the mid-racer very nicely and it had a tiller on it. At that time I was not running my little stubby bars either on my Vendetta. I rode the Vendetta for 3.0 around the track at 23.9 mph at 150 watts and I rode the M-5 Mid-racer around the same exact track (both solo) for 1.5 miles at 149watts. Ridiculous speed for that wattage but the conditions where perfect and on a smooth track. Low pressure and warm air. (Same day I rode my Vendetta on a 1HR TT at 28.4 on only 200 watts - fastest I have ever gone on so little watts). Here are my Strava files of the rides:
Vendetta at 150 watts: (lap #2) : https://www.strava.com/activities/354434413/laps
M5 - mid-racer at 149 watts: (lap #3): https://www.strava.com/activities/354434413/laps
1 Hr TT on same Vendetta at 200watts: https://www.strava.com/activities/354774841
